From 432732b801c82b139f8ca72e3b284fb999ac40d2 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Wed, 22 May 2019 14:47:31 -0500 Subject: [PATCH] soundwire: intel_init: add checks on link numbers Add mask to correctly read the SoundWire SHIM LCAP register. Only bits 2..0 are meaningful, the rest is about link synchronization and stream channel mapping. Without this mask, the hardware information would always be larger than whatever the BIOS would report. Also trap the case with zero links. Signed-off-by: Pierre-Louis Bossart Signed-off-by: Vinod Koul --- drivers/soundwire/intel_init.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/soundwire/intel_init.c b/drivers/soundwire/intel_init.c index 771a53a5c033..70637a0383d2 100644 --- a/drivers/soundwire/intel_init.c +++ b/drivers/soundwire/intel_init.c @@ -81,6 +81,7 @@ static struct sdw_intel_ctx /* Check SNDWLCAP.LCOUNT */ caps = ioread32(res->mmio_base + SDW_SHIM_BASE + SDW_SHIM_LCAP); + caps &= GENMASK(2, 0); /* Check HW supported vs property value and use min of two */ count = min_t(u8, caps, count); @@ -90,6 +91,9 @@ static struct sdw_intel_ctx dev_err(&adev->dev, "Link count %d exceeds max %d\n", count, SDW_MAX_LINKS); return NULL; + } else if (!count) { + dev_warn(&adev->dev, "No SoundWire links detected\n"); + return NULL; } dev_dbg(&adev->dev, "Creating %d SDW Link devices\n", count);